The present invention relates generally to a sleeve assembly for forming a lined opening in molded structures made for example from concrete and more particularly to such a sleeve assembly which may be arranged either between generally vertical, spaced-apart panels defining surfaces of a molded structure formed therebetween or may extend upwardly from a generally horizontal panel upon which the molded structure is formed.
In the formation of molded structures, particularly in concrete walls or the like, it is commonly necessary to provide a relatively large number of accurately located and shaped openings to permit the passage of conduits of various types through the finished structure. Normally, such structures are formed with one or more panels defining various surfaces of the structure. For example, a vertical concrete wall is generally poured between two spaced apart, vertically arranged panels while a floor may be similarly poured upon one horizontally arranged panel. The upper surface of the floor is normally finished manually.
In any event, it is desirable to be able to form and maintain openings through the structure in a relatively simple manner which does not interfere with formation of the structure. Some of the problems encountered in this regard include specific arrangement and shape of the openings to be formed in the structure. When the structure is formed from relatively heavy material such as concrete, the weight of the concrete being poured between the forms often tends to dislocate or deform elements intended to define an opening through the finished structure. In addition, when the opening is being formed through a horizontal structure such as the floor, it is desirable to provide means which may be readily installed upon a panel forming the bottom surface of the floor and remain in accurate alignment and extension thereabove during pouring or formation of the floor. Similarly, when the structure is being poured between two vertical forming panels, it is desirable that an element defining an opening through the structure be capable of simple and rapid installation between the panels while resisting the effect of forces developed during formation of the structure.